Strategy To Form Eutectic Molecular Liquids Based on Noncovalent Interactions

The concept of eutectic molecular liquids (EMLs) was defined, and a strategy to form EMLs based on noncovalent interactions was proposed. We verified the formation and investigated the properties, interaction sites, and interaction energies of the obtained 16 EMLs. Moreover, two new forms of noncovalent interactions, kappa-hole and mu-hole bonding interactions, were proposed, which broaden the understanding of intermolecular interactions. Numerous EMLs can be strategically designed and prepared by simply mixing two parent molecule components based on noncovalent interactions, including hydrogen bonding interactions; pi-pi stacking; and sigma-hole (halogen, chalcogen, pnicogen, and tetrel bonds), pi-hole, kappa-hole, and mu-hole bonding interactions. The properties of EMLs can be finely tailored by selecting or even designing appropriate parent compounds for task-specific applications. Our work presents a substantial step toward the innovative development of liquid systems.